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  <title>Document</title>
  <script>
    function countDown(time) {
      var nowTime = +new Date(); //返回的是当前时间总的毫秒数
      var inputTime = +new Date(time); //返回的是用户输入时间总的毫秒数
      var times = (inputTime - nowTime) / 1000; //times 是剩余时间总的毫秒数
      var d = parseInt(times / 60 / 60 / 24);   //天
      d = d < 10 ? '0' + d : d;
      var h = parseInt(times / 60 / 60 % 24);  // 时
      h = h < 10 ? '0' + h : h;
      var m = parseInt(times / 60 % 60);      // 分
      m = m < 10 ? '0' + m : m;
      var s = parseInt(times % 60);            //秒
      s = s < 10 ? '0' + s : s;
      return d + '天' + h + '时' + m + '分' + s + '秒';
    }
    console.log(countDown('2022-10-1 17:54:00'));
    var date = new Date();
    console.log(date);
  </script>
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